The present invention relates in general to recognition systems, particularly for recognising people.
The term "recognition" as used in the present description and, where appropriate, in the following claims, should be understood by its generally accepted meaning which includes, amongst other things, both the function currently known as "identification" the detection of the features of a person, the comparison of the data relating thereto with data, relating to identifying features of a plurality of people, stored in a data bank, and the subsequent identification of the person as one of the people whose features are stored in the data bank) and the function currently known as "verification" (ascertaining whether the features of the person being checked correspond to identification data previously stored and used as a template for comparison).
Recognition systems of the type specified above can be used, for example, for controlling access, for example, for "electronic concierge functions", in order to recognise employees working in small organisations (about 100 people); in this case small percentages of errors in the identification function are permitted.
Alternatively, systems of the type specified above may be used as systems for directly verifying and precisely ascertaining the identity of a certain person, whose identifying features are stored in the form of a template. In this case, however, it is not simply a question of checking to which of a plurality of previously stored templates the person in front of the system most probably corresponds, but, on the contrary, involves ascertaining in almost absolute terms that the person whose features are examined actually corresponds to a given person, for example, the only person or one of the few people authorised to have access to a certain area or to a certain service. A typical example of the application of a system of this type is that of controlling the opening of the door, for example, of a dwelling to which, naturally, it is desired to allow free access solely to residents. In these cases errors in recognising people are wholly unacceptable.
Naturally, the examples given above are only two of the possible applications of systems of the type specified above. These systems may be used, for example, for carrying out alternative (or additional) functions in relation to the supply of a password for access to a certain service, for example, by means of a terminal of a data-processing system, or even for systems for carrying out transactions automatically, such as electronic banking machines (BANCOMAT etc.). Clearly, in all the applications described above, the minimising of the possible margins of error is an imperative requirement.